来自New Bing的题解（未优化）

#include <iostream>
#include <algorithm>

using namespace std;

const int N = 5010;

struct Student
{
    int id;
    int score;
}stu[N];

bool cmp(Student a, Student b)
{
    if(a.score != b.score) return a.score > b.score;
    else return a.id < b.id;
}

int main()
{
    int n, m;
    cin >> n >> m;

    for(int i = 0; i < n; i ++ )
        cin >> stu[i].id >> stu[i].score;

    sort(stu, stu + n, cmp);

    int line = stu[(m * 3 / 2) - 1].score;

    while(stu[m - 1].score >= line) m ++ ;

    cout << line << ' ' << m - 1 << endl;

    for(int i = 0; i < m - 1; i ++ )
        cout << stu[i].id << ' ' << stu[i].score << endl;

    return 0;
}